Danfoss DHP-H, Installation And Service Instructions Manual

Page: 42 / 96

42
VMBMA602
12.4 Passive cooling function, DHP-C
Heat pump DHP-C is equipped with an extra heat exchanger to use the passive cooling effect from the brine. Because the temperature in
the collector (borehole or equivalent) is lower than the indoor temperature, the temperature difference can be exploited to cool the indoor
air. At the same time the collector is charged with energy before the cold periods of the year.
DHP-C is a complete installation for heating, hot water and passive cooling where the control automatically ensures that the desired indoor
climate is reached. Because the DHP-C uses the same pipe system for heating and cooling, it is important to use a temperature when cool-
ing that does not cause condensation on the pipe system. (If the system is not adapted to it.) Use of fan convectors is recommended.
12.5 Speed control, Opti models
A heat pump requires optimum conditions in the heating system and brine circuit in order to be able to run as efficiently as possible. The
temperature difference between the heating system’s supply line and return line must be constant between 7–10°C. For the brine circuit a
temperature difference of 3°C between supply and return line applies. If the differences are greater or less, the heat pump is less efficient
and savings are lower.
A heat pump with speed controlled circulation pumps always ensures that they retain the temperature differences. The control equipment
detects if the balance is in jeopardy and increases or decreases the speed of the circulation pumps as necessary.
12.6 HGW technology, DHP-H Opti Pro
The HGW technique is a new and unique method for hot water heating, which is used in DHP-H Opti Pro. At the same time as the water
is heated to be distributed around the house heating system, a small proportion flows via an extra de-superheater, which heats the water
before it enters the water heater. The exchange valve that controls the flow between hot water and heating system is replaced with a shunt
(HGW shunt).
During heating production, the HGW shunt ensures that a flow over the de-superheater to the water heater. The flow through the shunt is
continuously regulated by the heat pump control by sending opening or closing pulses to the shunt.
12.7 Auxiliary heating, DHP-H, -L, -C
If the heat demand is greater than the heat pump’s capacity, the auxiliary heater engages automatically. The auxiliary heater is made up of
an electric heating element on the supply line that has two outputs, AUX. HEAT 1 and AUX. HEAT 2, and can be controlled in three steps.
For three phase, 400V 3N, installations:
• Step 1 = AUX. HEAT 1 = 3 kW
• Step 2 = AUX. HEAT 2 = 6 kW
• Step 3 = AUX. HEAT 1 + AUX. HEAT 2 = 9 kW
For single phase, 230V 1N, installations (not DHP-C):
• Step 1 = AUX. HEAT 1 = 1,5 kW
• Step 2 = AUX. HEAT 2 = 3 kW
• Step 3 = AUX. HEAT 1 + AUX. HEAT 2 = 4.5 kW
In the event of an alarm, the auxiliary heater engages automatically.
12.8 Auxiliary heating DHP-A, -AL
The auxiliary heater for 400V 3N heat pumps is made up of an electric heating element on the supply line that has three outputs, AUX.
HEAT 1, AUX. HEAT 2 and AUX. HEAT 3, and can be controlled in five steps:
• Step 1 = AUX. HEAT 1 = 3 kW
• Step 2 = AUX. HEAT 2 = 6 kW
• Step 3 = AUX. HEAT 1 + AUX. HEAT 2 = 9 kW
• Step 4 = ADD.HEAT 2 + ADD.HEAT 3 = 12 kW (only connected at switched off compressor)
• Step 5 = ADD.HEAT 1 + ADD.HEAT 2 + ADD.HEAT 3 = 15 kW (only connected at switched off compressor)
• Step +4 = ADD.HEAT 2 + ADD.HEAT 3 = 12 kW (compressor operation permitted)
• Step +5 = ADD.HEAT 1 + ADD.HEAT 2 + ADD.HEAT 3 = 15 kW (compressor operation permitted)
The two power steps, step 4 and step 5, cannot be activated when the compressor is running. There are further auxiliary heating steps: step
+4 and step +5, which means that these additional steps can be activated whilst the compressor is running. Step +4 and +5 must only be
selected on the condition that the building where the heat pump is installed has a large heating demand and the building’s electric instal-
lation is suitable for high current consumption.
The auxiliary heater for 230V 1N heat pumps is made up of an electric heating element on the supply line that has two outputs, AUX. HEAT
1 and AUX. HEAT 2, and can be controlled in three steps:
• Step 1 = AUX. HEAT 1 = 1,5 kW
• Step 2 = AUX. HEAT 2 = 3 kW
• Step 3 = AUX. HEAT 1 + AUX. HEAT 2 = 4.5 kW
In the event of an alarm, the auxiliary heater engages automatically.